Navigation System Symptom Troubleshooting - Audio-navigation unit button illumination does not work(With Display Audio)

NOTE: 

• Check the vehicle 12 volt battery condition first .
• Check for B-CAN DTCs and resolve them before troubleshooting.
• Check the connectors for poor connections or loose terminals.

• 1. Problem verification:

  - 1. Turn the vehicle to the ON mode.

  - 2. Turn the combination light switch to the parking light position.

  - 3. Check the illumination of the audio-navigation unit buttons.

  Are the buttons illuminated?

  YES 

  Intermittent failure, the audio unit is OK at this time.

  NO 

  The failure is duplicated, go to step 2.

• 2. Determine possible failure area (interior lights circuit, others):

  - 1. Check the illumination of several other buttons not related to the audio/navigation system.

  Are the buttons illuminated?

  YES 

  Go to step 3.

  NO 

  Troubleshoot the interior lights.

• 3. Determine possible failure area (audio-navigation unit, others):

  - 1. Go into the System Diagnostic Mode, and use the Vehicle Status to check the ILLUMI signal .

  Does the ILL signal change from [0] to [1] when the combination light switch is turned to the parking light position?

  YES 

  Replace the audio-navigation unit .

  NO 

  Go to step 4.

• 4. Open wire check (B-CAN_H line, B-CAN_L line):

  - 1. Turn the combination light switch off.

  - 2. Turn the vehicle to the OFF (LOCK) mode.

  - 3. Disconnect the following connectors.

  Gauge control module connector A (32P)

  Audio-navigation unit connector C (20P)

  - 4. Check for continuity between test points 1 and 2.

  Test condition	Vehicle OFF (LOCK) mode
  	Gauge control module connector A (32P): disconnected
  	Audio-navigation unit connector C (20P): disconnected
  Test point 1	Gauge control module connector A (32P) No. 30
  Test point 2	Audio-navigation unit connector C (20P) No. 13

  Test point 1	Gauge control module connector A (32P) No. 31
  Test point 2	Audio-navigation unit connector C (20P) No. 3

  Is there continuity?

  YES 

  Replace the audio-navigation unit .

  NO 

  Repair an open in the wire(s) between the audio-navigation unit and the gauge control module.